ovito: command not found

Maybe Your $PATH variable doesn't contain the default paths? echo $PATH should give something like:

[root@server ~]# echo $PATH
/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin:/root/bin

If it's empty, You may set the PATH variable with this command

export PATH="/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin:/root/bin"

On Debian possible default full paths are:

/usr/bin/ovito - from package: ovito

You may install the required package with command apt-get install {package}

Error in other languages:
ovito: bevel nie gevind nie
ovito: comandă negăsită
ovito: comando não encontrado
ovito: commande introuvable
ovito: command not found
ovito: käsku ei ole
ovito: không tìm thấy lệnh
ovito: komanda nerasta
ovito: Kommando nicht gefunden.
ovito: kommandot finns inte
ovito: komut yok
ovito: nie znaleziono polecenia
ovito: níor aimsíodh an t-ordú
ovito: no se encontró la orden
ovito: no s'ha trobat l'ordre
ovito: opdracht niet gevonden
ovito: parancs nem található
ovito: perintah tidak ditemukan
ovito: príkaz nenájdený
ovito: příkaz nenalezen
ovito: команда не найдена
ovito: командата не е открита
ovito: 命令找不到
ovito: コマンドが見つかりません